What's the task of the script? If your character is just running around on a small area such as smithing ores at the Edgevile furnace and then banking/withdrawing from the bank nearby then it should only eat an amount of 100K to 150K of RAM memory usage. Otherwise, if the script does multiple tasks such as travelling into the dungeon, involves teleportation and running around long distant places then it is just normal to have a memory consumption of 500K to 600K.